Stretching exercises, special pillows and acupuncture could help relieve back and pelvic pain that often occur during pregnancy, according to an updated review.

As pregnancy progresses, back and pelvic pain can interfere with daily activities such as carrying groceries, cleaning and walking, and can disrupt work or sleep also. More than two-thirds of pregnant women experience back pain and almost one-fifth report pelvic pain.

“When you’re pregnant, your center of gravity is off. You have to arch your back to balance this huge tummy, so you end up with extra strain on your back and pelvic muscles,” said Victoria Pennick, M.H.Sc., registered nurse and lead review author.

Women who participated in a variety of intervention programs recognized some relief of back and pelvic pain, said Pennick, a senior clinical research project manager at the Institute for Work & Health in Toronto. The review looked at eight studies that examined the effect of adding pregnancy-specific strengthening exercises, water exercises, acupuncture and other pain-relief interventions to regular prenatal care. None of the studies dealt specifically with back or pelvic pain prevention.

The review appears in the current issue of The Cochrane Library, a publication of The Cochrane Collaboration, an international organization that evaluates research in all aspects of health care. Systematic reviews draw evidence-based conclusions about medical practice after considering both the content and quality of existing trials on a topic.

Although the conclusions of this update did not differ significantly from previous 1998 and 2002 reviews, Pennick noted the addition of five trials available for analysis.

“We were able to group trials about women who had back pain alone, women who had pelvic pain alone and both. You don’t have that luxury when you have only three studies,” as in the earlier reviews, Pennick said.

The review authors found that women who participated in prenatal exercise programs reported significant decreases in back pain compared to women who received the usual prenatal care.

In one study that evaluated work absenteeism during pregnancy, only 12.9 percent of the pregnant women who participated in water gymnastics missed work due to low-back pain, compared with 21.7 percent of the women who received usual prenatal care.

Another study evaluated whether a special pillow called the Ozzlo pillow, a curved, soft cushion designed to support the pregnant abdomen when lying down, reduced back pain. Although manufacturers no longer make the pillow, it proved superior to a regular pillow in relieving back pain in pregnant women.

In one study of women with both back and pelvic pain, 60 percent who received acupuncture reported less intense pain, compared to 14 percent of women who did not. The study found no complications associated with the use of acupuncture in pregnant women.

On average, women who followed through with the pelvic or back pain interventions experienced some pain relief and reported less need for pain medication, physical therapy and posture-support belts.

However, “given the level of scientific rigor by which these studies were done, you have to be cautious,” Pennick said. The big question that these studies did not address was why some pregnant women failed to follow through with the exercises or other interventions, she said.

“It’s very difficult to turn around and say ‘this intervention works better than that one’ because you didn’t have that level of certainty in the studies,” Pennick said.

Shu-Ming Wang, M.D., associate professor in the department of anesthesiology at Yale School of Medicine, said that the analysis appeared to be well-conducted, but cautioned readers that there is a paucity of high-quality clinical trials to examine the various interventions mentioned.

Wang, who conducts research on low back pain management in pregnant women funded by the National Center for Complementary and Alternative Medicine, did not participate in the Cochrane review.

Both Pennick and Wang urged caution to women considering interventions to reduce back or pelvic pain during pregnancy, especially those that they didn’t use before conception.

“For example, if you’ve never had acupuncture, it may not be the intervention of choice for you. It’s really important to talk it over with your own primary care provider and decide together what’s right for you,” Pennick said.